solar fuse size

[Bolti]

I have upgraded my solar panel from 100w to 200w.

The fuses between the panel and controller, and controller to batteries are 10A.

Do these now need to be larger? I have also replaced the wiring from controller to battery with 6mm.

Thanks in advance.

 

[Jev88]

I am sure better advice will come along but what did the max ampage sticker say in the panel?

 

[Raul]

If the controller is a MPTT, 200w divided by 12v gives 16,66A. So your controller to battery should have at least 15A fuse. From panel to controller it should be the Imp on the panel value.

 

[Bolti]

If the controller is a MPTT, 200w divided by 12v gives 16,66A. So your controller to battery should have at least 15A fuse. From panel to controller it should be the Imp on the panel value.

I am sure better advice will come along but what did the max ampage sticker say in the panel?

Imp is 10.8A so am I right in thinking the 10 amp fuse is ok for panel to controller.
The controller is a votronic 250 MPPT so will try a 15A. Thanks for your help.

 

[tonka]

If the controller is a MPTT, 200w divided by 12v gives 16,66A. So your controller to battery should have at least 15A fuse. From panel to controller it should be the Imp on the panel value.

BUT Solar panels to controller do not give out 12v.. Most are around 18-21v..
The regulator changes that into 12v (ish).

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[Raul]

If it’s not a solar fuse, the 10a will be ok. If it’s a solar fuse gPV 10x38, then it should be a 12a. The solar fuses are ultra fast blow, and it will blow if it’s to small, on transient sun or cloud lensing.
As a note, on one panel, a switch is enough, no need to fuse a single panel.

 

[Raul]

BUT Solar panels to controller do not give out 12v.. Most are around 18-21v..
The regulator changes that into 12v (ish).

The solar controller IS the regulator, and will give out the battery voltage is connected to. What you are referring to, is the voltage IN (18-21) for 36cell panels. My solar kicks 50+ volts into the controller, and out 13-14,2v. Because that’s the battery voltage.
What you did not understand is, the total amps from controller to battery. Thats why I mentioned MPTT. The mppt works as: power in power out.
So 200w divided by 19,5Vmp= 10,25A that’s what controller receives.
What comes out of controller is same 200w divided by the battery voltage.

 

[autorouter]

You do realize, I hope, that a solar panel can not blow a fuse that is big enough to let normal power through. Compare the maximum power amps with the short circuit amps, there is hardly any difference. It's not like a battery, where a short circuit can result in hundreds if not thousands of amps.